Biochemical testing for research and diagnostic applications can require simultaneous assays including a large number of analytes in conjunction with one or a few samples. Further, biochemical testing can include extended sample manipulation, multiple test substrates, multiple analytical instruments, and other steps. It may be desirable to analyze one or a few biological samples using a single test device with a large number of analytes while requiring a small amount of sample. It also may be desirable to load one or more biological samples into one or more sample chambers of a substrate and individually seal each chamber while performing a chemical reaction, such as, for example, a polymerase chain reaction (PCR) in the chamber and/or while otherwise processing the sample, including, for example, sample preparation.
Isolation (e.g., sealing) of biological sample and/or chemical assays within a substrate or other biological testing device may be desirable to perform chemical reactions and to avoid cross-contamination of various substances within a biological testing device, such as, for example, a microfluidic substrate which defines a network of sample distribution channels and chambers. Various techniques have been used to achieve sealing, for example, of channels and/or chambers of microfluidic substrates, including, for example, mechanically deforming a laminate layer of the substrate.
It may be desirable, however, to provide a mechanism for achieving sealing of chambers and/or channels in a microfluidic device that is reversible and/or selectively actuatable, which may thereby permit serialized processing and/or flow control of the sample, for example, within a microfluidic substrate for biological testing. It may further be desirable to provide a mechanism for achieving sealing that permits a closure force to be adjusted. Additionally, it may be desirable to provide a relatively inexpensive mechanism to achieve sealing that is relatively easy to manufacture.
Moreover, it may be desirable to provide a method and device that achieves valving (e.g., control over fluid flow) within a microfluidic device, for example, a microfluidic device for performing biochemical testing.
It also may be desirable to provide mechanisms that achieve sealing and/or valving that do not rely on mechanical and/or external actuation devices and/or that reduce wear.